| With the rapid development of science and technology, application of ultra-precision micro-structure is becoming more and more widespread. Therefore, with the micro-structure of the mold manufacturing has become the hot topic now. Due to the continuous rolling in the industrialized production, roller mold has become the mainstream of mold with high efficiency. But turning equipment is more sophisticated than general one, and cutting step length is less than tool radius, which results in the low efficiency of single point diamond turning, and waste a lot of time in production process. Therefore, insuring machining accuracy and surface roughness as the premise, time cost should be reduced as far as possible.This paper selected micro-V structure and four pyramid structure as research object. Traditional method intermittent turning of micro-V structure was analyzed, and improved method continuous turning of micro-V structure was put. After cutting tool path analyzed, the efficiency of improved method was higher than traditional one. Due to the continuous turning method would have error in the rolling process, this paper re fered to the helix angle a as the characterization of this error. When the roller diameter was 500mm, the error in the rolling process was 0.00073°, meant after rolling 100mm, the deviation of the structure was 1 u m, which was under the control of the rolling replication error range.Applying the spiral continuous turning method in the four pyramid structure, oblique 45° method of four pyramid structure and orthogonal method of four pyramid structure were put. The good and the bad of two turning methods and the time cost were analyzed. The results showed that the efficiency of orthogonal method is higher than the oblique 45°. Dividing error would produce on the roller end face, which refered to mean error εeq. When the width of the four pyramid was 30μm, turning time on roller end face was 15800, the average error of each structure was 60.46nm, which compared to the size of structure is more smaller, almost negligible.Finite element software ABAQUS was used to simulate the cutting force of tool in turning process. Three commonly used materials is selected to do the simulation. The results showed that the cutting force of the tool was the biggest of the three when turning nickel phosphorus alloy MP35N, but because of the characteristics of nickel phosphorus alloy MP35N, the mold material always choose this one. Turning simulation with cutting depth and cutting speed was conducted, which founded that cutting force will increase with the increase of cutting depth and cutting speed, and the effect of cutting depth on cutting force was larger.In order to verify the validity of spiral continuous turning method of micro-V structure, aluminum 6061 turning experiment was conducted, and the micro-V structure surface was detected by 3D laser microscope, which could obtain three groups surface roughness of micro-V structure. Dynamic modeling from NC turning system was built by Matlab/Simulink. Tool-Z axis after turning system Would produce vibration, which could affect the workpiece surface roughness. The surface roughness R value could obtain from the simulation, compared with surface roughness from the experiment. Two errors were controlled with 10%, which could prove the validity of the simulation model. |
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